Problem configuring Aironet 1200 as repeater

I wonder whether anyone can help with a problem that I am having with
trying to set up an Aironet 1200 as a repeater.

I have a number of Aironet 1200 APs installed in a number of locations,
all working happily. I now need to deliver wireless coverage to a small
location that cannot be wired into, so I thought of using another 1200 as
a repeater.

I have set up a lab test comprising a 1200 running in root mode and a
second 1200 configured as a repeater. There is a PIX acting as the
gateway to the outside world and providing a DHCP service for the wireless
clients.

If I place a client lap-top near to the root AP so that the lap-top
associates with the root AP, everything works as expected (with the
unexpected exception that I am unable to access the web management
interface in the repeater AP or even ping it).

If I then move the client lap-top near to the repeater AP, it associates
with the repeater fine. At this point I can now connect to the web
management interface in both the root and the repeater access point.
However, I can no longer ping the lap-top's default gateway and,
obviously, all connectivity to the outside world is lost. Nor am I able
to ping any other IP on the wired part of the subnet (for example, the
switch management interface). However, I am still able to release and
renew the DHCP lease on the lap-top.

If I reassociate the lap-top with the root AP, the original situation is
restored: I can access hosts on the wired part of the network and I can
access the outside world all as expected, but I can no longer ping the
repeater AP.

I have reviewed the Cisco document 'Configuring Repeater and Standby
Access Points', and believe I have done everything necessary to configure
the repeater correctly. [The document refers to the non-existent 'dot11
extensions aironet' command. The command appears actually to be 'dot11
extension aironet'. Aironet extensions are turned on as reported by the
web GUI in both the root and repeater APs, but the command does not appear
to reflect back in the running-config.] The config files are below, with
some details omitted to protect the innocent.

Both APs are running 12.2(13)JA3 and both have 802.11g radios with the
cardbus radio slot unoccupied.

On the client side, I have tried Win XP Pro SP1 with a Cisco 340 card and
Win 2000 Pro SP4 with the same 340 card, and also with a Linksys WPC11
version 3, and with an ORiNOCO Gold. The results are the same in all
cases.

When the client is associated with the repeater, the network map on the
root AP shows the repeater, as does the adjacent AP list also. The
association page shows the repeater device type as 'ap1200-Rptr' and it
shows the client as device type 'Rptr-client'.

At the same time, the network map on the repeater AP shows both itself and
the root AP as device 'Access-Point'. The Adjacent AP list is, however,
empty. The association page shows the root AP as device type
'ap1200-Parent' and the client as '240-client'.

Root AP config:

Repeater AP config:

Can anyone offer any suggestions?

Tim Levy
London

 

Have you tried changing the default gateway so it is in the 172.25.30.0/24 subnet ?

 

See if removing the "dot11 arp-cache" has any effect

BTW the dot11 arp-cache feature is supported on repeater by the
12.2(15)JA release

 

Thanks for pointing this out. I should have spotted it in the release
notes, but must have been suffering from a momentary lapse of reason:

12.2(13)JA4:
CSCec72841 - The ARP cache feature is not supported on repeater access points.

12.2(15)JA:
CSCec72841 - The ARP cache feature is now supported on repeater access points.

Anyway, turning off the dot11 ARP cache on APs with 12.2(13) made the
problem I described in my OP go away.

Thanks again.

 

Your welcome

Merv Hrabi
CCIE# 4169